The MXL AC-400 is a personal USB web conferencing microphone that is perfect for conference calls. The AC-400 facilitates clear, intelligible communication over the internet from a desktop or laptop computer in any workspace. Because it is a personal mic, the AC-400 records only the speaker and not surrounding sounds. With the outstanding voice clarity, it will sound almost as if you are speaking face to face with someone in another building, another state, or another country. Use the AC-400 with web conferencing software, voice recognition software and dictation software. The durable, all-metal construction of this microphone makes it suitable for any office environment. The AC-400 features a headphone jack and a mute button. The MXL AC400 works well by itself or it can be used with up to three optional AC-40EXT mics to include more people in the conversation.